package httpapi

import (
	"errors"
	"net/http"
	"strconv"
	"strings"

	"github.com/descrybe/descrybe-v2/apps/api/internal/company"
	"github.com/descrybe/descrybe-v2/apps/api/internal/security"
	"github.com/go-chi/chi/v5"
	"github.com/google/uuid"
)

const brandLogoMaxUpload = 3 << 20 // parse budget slightly above 2 MiB file cap

func (s *Server) handleUploadBrandLogo(w http.ResponseWriter, r *http.Request) {
	cid, _ := CompanyIDFromContext(r.Context())
	role, _ := RoleFromContext(r.Context())
	if role != "admin" {
		Error(w, http.StatusForbidden, "admin required")
		return
	}

	if err := r.ParseMultipartForm(brandLogoMaxUpload); err != nil {
		Error(w, http.StatusBadRequest, "invalid multipart form")
		return
	}
	file, header, err := r.FormFile("file")
	if err != nil {
		file, header, err = r.FormFile("logo")
	}
	if err != nil {
		Error(w, http.StatusBadRequest, "file field required")
		return
	}
	defer file.Close()

	logoURL, _, _, _, err := company.SaveBrandLogo(
		s.Config.UploadDir,
		cid,
		header.Filename,
		header.Header.Get("Content-Type"),
		file,
	)
	if err != nil {
		ClientOrLog(w, http.StatusBadRequest, "could not upload logo", err, company.ClientError)
		return
	}

	current, err := company.LoadBrand(r.Context(), s.Pool, cid)
	if err != nil {
		Error(w, http.StatusInternalServerError, "load brand failed")
		return
	}
	current.LogoURL = logoURL
	saved, err := company.UpsertBrand(r.Context(), s.Pool, cid, current)
	if err != nil {
		Error(w, http.StatusInternalServerError, "save brand failed")
		return
	}
	s.brandResponse(w, r, saved)
}

func (s *Server) handleGetBrandLogoFile(w http.ResponseWriter, r *http.Request) {
	cid, _ := CompanyIDFromContext(r.Context())
	name := chi.URLParam(r, "filename")
	s.serveBrandLogo(w, r, cid, name)
}

func (s *Server) handlePublicBrandLogo(w http.ResponseWriter, r *http.Request) {
	companyRaw := chi.URLParam(r, "companyID")
	cid, err := uuid.Parse(companyRaw)
	if err != nil {
		Error(w, http.StatusBadRequest, "invalid company id")
		return
	}
	name := chi.URLParam(r, "filename")
	expRaw := strings.TrimSpace(r.URL.Query().Get("exp"))
	sig := strings.TrimSpace(r.URL.Query().Get("sig"))
	exp, err := strconv.ParseInt(expRaw, 10, 64)
	if err != nil {
		Error(w, http.StatusForbidden, "invalid or expired signature")
		return
	}
	secret := strings.TrimSpace(s.Config.TokenSigningSecret)
	if secret == "" {
		Error(w, http.StatusServiceUnavailable, "signed logos unavailable")
		return
	}
	if err := company.VerifyPublicBrandLogoSig(secret, cid, name, exp, sig); err != nil {
		Error(w, http.StatusForbidden, "invalid or expired signature")
		return
	}
	s.serveBrandLogo(w, r, cid, name)
}

func (s *Server) serveBrandLogo(w http.ResponseWriter, r *http.Request, companyID uuid.UUID, name string) {
	f, contentType, err := company.OpenBrandLogo(s.Config.UploadDir, companyID, name)
	if err != nil {
		switch {
		case errors.Is(err, company.ErrLogoInvalidName), errors.Is(err, company.ErrLogoForbidden):
			Error(w, http.StatusBadRequest, "invalid logo path")
		case errors.Is(err, company.ErrLogoNotFound):
			Error(w, http.StatusNotFound, "logo not found")
		default:
			Error(w, http.StatusInternalServerError, "could not open logo")
		}
		return
	}
	defer f.Close()

	st, err := f.Stat()
	if err != nil {
		Error(w, http.StatusInternalServerError, "could not stat logo")
		return
	}
	w.Header().Set("Content-Type", contentType)
	w.Header().Set("Cache-Control", "private, max-age=3600")
	w.Header().Set("X-Content-Type-Options", "nosniff")
	http.ServeContent(w, r, name, st.ModTime(), f)
}

func isBrandLogoURLError(err error) bool {
	return errors.Is(err, security.ErrInvalidURL) ||
		errors.Is(err, security.ErrBlockedURL) ||
		errors.Is(err, security.ErrBlockedHost) ||
		errors.Is(err, company.ErrLogoInvalidName)
}